My dad has an Asus G73Jh that we got off craigslist a few weeks back. The GPU is faulty and when it's under load the system shuts off, but that's a separate problem. We hooked it up to the TV to watch a movie with the video going through VGA and the audio going to the AV receiver via 3.5mm to RCA. While charging a quite loud squealing/whining sound can be heard, and there is some faint static horizontal lines in the middle of the picture. When you unplug the charger both effects vanish. I also noticed on a recent road trip that something similar happens with my Acer netbook. While plugged into the power inverter, a squealing could be heard through the headphones. What could be causing this? Possibly sound drivers or "dirty" power coming from the source or chargers?